RAF Menwith Hill, run by NSA, is
the biggest surveillance facility in Europe

Claims by US whistleblower J.
Kirk Wiebe dragged Britain into scandal

Base works closely with Britain’s
own top-secret listening station, GCHQ

The United States used a British spy base to listen in on the phone
calls of Angela Merkel and 35 other world leaders, it was claimed last
night.

RAF Menwith Hill in North Yorkshire, which is run by America’s
National Security Agency (NSA), is the biggest surveillance and
interception facility in Europe.

The base analyses satellite signals as well as mobile phone and
electronic data from private individuals, governments and corporations.

Concern: RAF Menwith Hill in Yorkshire has now been dragged inot the
intelligence scandal

Last week it was reported that American spies had been listening in
on the phone conversations of dozens of world leaders.

Claim: NSA whistleblower J Kirk Wiebe implicated the British base

The allegations led Mrs Merkel to call Barack Obama and ask him to
account for his agents’ actions.

Now fresh claims by US whistleblower J. Kirk Wiebe, who worked for
the NSA for 30 years, have dragged Britain into the scandal.

Mr Wiebe believes US agents used the base to intercept the German
leader’s phone calls – with the full knowledge of British officials.

He told The Mail on Sunday it was
likely agents at Menwith Hill ‘either directly collected the data or
would have processed data’ from the bugged calls before sending the
information back to Washington.

Mr Wiebe, who left the NSA in 2001
over fears it was illegally gathering ‘huge swathes’ of electronic data
from citizens in the US and globally, said: ‘If the information didn’t
come from there, it is almost a certainty that it would have been
processed there.’

He added: ‘Everything goes through
there to be analysed before the information is sent back to Washington.'

Menwith Hill, which has 33 distinctive
golf ball-shaped ‘radomes’ to house satellite dishes, was effectively
handed over to the Americans in the 1950s in recognition of the
important intelligence-sharing relationship between the two countries.
The base works closely with Britain’s own top-secret listening station,
GCHQ in Cheltenham.

Committee: Former Liberal Democrat leader Sir Menzies
Campbell said there needed to be a 'robust and easily understood legal
system of control'

Any information processed or analysed
at Menwith Hill is then sent back to NSA headquarters in Fort Meade,
Washington. The Ministry of Defence insists Ministers are ‘fully briefed
on the activities at RAF Menwith Hill’.

But concerns have long been expressed
about the lack of scrutiny US spying operations face when they are
carried out on British soil.

Responding to calls for greater
transparency, the Commons’ Intelligence and Security Committee – whose
members are among a select group of British politicians with security
clearance to visit the site – has promised to review the laws that keep
a check on intelligence-gathering by Britain.

Former Liberal Democrat leader Sir
Menzies Campbell, one of the MPs who sits on the committee, said there
needed to be a ‘robust and easily understood legal system of control’.

Listening in: Last week it was
reported that the USA had listened in on world leaders including
Angela Merkel (pictured)

He told The Mail on Sunday that the
current system of regulation was set up before some of the ‘far-reaching
capabilities of intelligence-gathering’ were in existence.

Sir Menzies said: ‘Parliament must
therefore be ready to review whether the existing legislation is good
enough. When it comes to relations with other countries there is a
well-established relationship between the five eyes – the UK, USA,
Canada, Australia and New Zealand.

‘Of these relationships, the one
between the UK and the US is by far the strongest. But no matter the
strength of any relationship, the responsibility for legality and for
review must always rest with domestic government.’

Documents leaked by NSA whistleblower
Edward Snowden in June revealed how spies based at Menwith Hill managed
to intercept Dmitry Medvedev’s calls as the former Russian president
visited Britain for the G20 summit in 2009.

But Mr Wiebe’s claim suggests that the
base is used to intercept calls from politicians all over Europe, not
just those who are visiting the UK. The Ministry of Defence said: ‘We
do not comment on intelligence matters.’